Research Projects

ent-kaurane diterpenoids are known to show interesting biological activities and based on its structural features, ent-kaurane diterpenoids were classified into different sub-classes: the C-20 non-oxygenated ent-kauranoids, the C-20 oxygenated ent-kauranoids, the seco-ent-kauranoids, nor- or rearranged ent-kauranoids, and grayananes. A general synthetic strategy for synthesizing structurally diverse and biologically active ent-kaurane diterpenoids by functionalizing easily accessible enantiomerically enriched Wieland-Miescher ketone derivative has been proposed. ent-Kauranoids exhibit numerous frameworks and oxidation patterns, as well as a variety of bioactivities, and so these molecules have naturally attracted wide attention from synthetic chemists and few total syntheses were disclosed over the past decade. It was contemplated that ent-kaurene skeleton could be easily accessible using Wieland-Miescher ketone derivative as a starting material. The Weiland-Miescher ketone contains the AB-ring structure of steroids and is for this reason an attractive starting material for the steroid skeleton. We have also designed the synthetic strategy for the construction of biologically active diterpenoids containing intriguing architectures such as euphoranginol C, and euphoranginone D. By implementing the same strategy, the other ent-Kaurane diterpenoids, liangshanin G, ent-11β and ent-11α-hydroxy-16-kaurene, and platensimycin can be easily synthesised. The novel synthetic route for the synthesis of ent-Kaurane D has been designed using Pd-mediated 5-exo oxidative cyclization, chemoselective reduction followed by Barton-McCombie de-oxygenation, deketalization, and intramolecular aldol condensation.